1. Field of the Invention
The present invention is directed to a torsional vibration damping arrangement for a drivetrain of a vehicle, having an input region driven in rotation around an axis of rotation and an output region. Provided between the input region and the output region are a first torque transmission path and parallel thereto a second torque transmission path and a coupling arrangement for superposing the torques guided via the torque transmission paths. A phase shifter arrangement is provided in the first torque transmission path for generating a phase shift of rotational irregularities guided via the first torque transmission path relative to rotational irregularities guided via the second torque transmission path.
2. Detailed Description of Prior Art
A generic torsional vibration damping arrangement known from German Patent Application DE 10 2011 007 118 A1 divides the torque introduced into an input region through a crankshaft of a drive unit, into a torque component transmitted via a first torque transmission path and a torque component guided via a second torque transmission path. Not only is there a static torque divided in this torque division, but the vibrations and rotational irregularities which are generated by the periodically occurring ignitions in a drive unit and contained in the torque to be transmitted are also divided proportionately into the two torque transmission paths. The torque components transmitted via the two torque transmission paths are brought together again in a coupling arrangement which can be constructed as a planetary gear set with a planet gear carrier and are then introduced as a total torque into the output region a friction clutch or the like.
A phase shifter arrangement having an input element and an output element is provided in at least one of the torque transmission paths. This phase shifter arrangement is constructed in the manner of a vibration damper, i.e., has a primary side and a secondary side rotatable with respect to the primary side through the compressibility of a spring arrangement. In particular when this vibration system passes into a supercritical state, i.e., when it is excited with vibrations exceeding the resonant frequency of the vibration system, a phase shift of up to 180° occurs. This means that at maximum phase displacement the vibration components proceeding from the vibration system are shifted in phase by 180° with respect to the vibration components received by the vibration system. Since the vibration components guided via the other torque transmission path do not undergo a phase shift or, if so, a different phase shift, the vibration components which are contained in the unified torque components and which are then shifted in phase with respect to one another are destructively superposed on one another such that, ideally, the total torque introduced into the output region is a static torque which contains essentially no vibration components.